[ODRHash] Skip more types hashing TypedefType

To get the underlying type for TypedefType's, also skip ElaboratedType's.

llvm-svn: 329869

clang/lib/AST/ODRHash.cpp

@@ -646,9 +646,19 @@ public:
     AddDecl(T->getDecl());
     QualType UnderlyingType = T->getDecl()->getUnderlyingType();
     VisitQualifiers(UnderlyingType.getQualifiers());
-    while (const TypedefType *Underlying =
-               dyn_cast<TypedefType>(UnderlyingType.getTypePtr())) {
-      UnderlyingType = Underlying->getDecl()->getUnderlyingType();
+    while (true) {
+      if (const TypedefType *Underlying =
+              dyn_cast<TypedefType>(UnderlyingType.getTypePtr())) {
+        UnderlyingType = Underlying->getDecl()->getUnderlyingType();
+        continue;
+      }
+      if (const ElaboratedType *Underlying =
+              dyn_cast<ElaboratedType>(UnderlyingType.getTypePtr())) {
+        UnderlyingType = Underlying->getNamedType();
+        continue;
+      }
+
+      break;
     }
     AddType(UnderlyingType.getTypePtr());
     VisitType(T);

clang/test/Modules/odr_hash.cpp

@@ -2744,6 +2744,38 @@ struct S3 {
 #else
 S3 s3;
 #endif
+
+#if defined(FIRST)
+using A4 = int;
+using B4 = A4;
+struct S4 {
+  B4 x;
+};
+#elif defined(SECOND)
+using A4 = int;
+using B4 = ::MultipleTypedefs::A4;
+struct S4 {
+  B4 x;
+};
+#else
+S4 s4;
+#endif
+
+#if defined(FIRST)
+using A5 = int;
+using B5 = MultipleTypedefs::A5;
+struct S5 {
+  B5 x;
+};
+#elif defined(SECOND)
+using A5 = int;
+using B5 = ::MultipleTypedefs::A5;
+struct S5 {
+  B5 x;
+};
+#else
+S5 s5;
+#endif
 }  // MultipleTypedefs
 
 namespace DefaultArguments {